As is known, current radiators suitable for heating one or more rooms comprise a battery of mutually associated radiating elements inside which a hot fluid, for example a diathermic oil, is contained; and is heated by an electric resistor.
In this type of radiator, heat propagation occurs essentially in two ways: by conduction and by convection.
Heat propagation by conduction occurs between the internal surfaces of the oil radiator which are in contact with the hot fluid and the outer surfaces, which despite being spaced from the hot fluid, in a short time reach the same temperature as the fluid.
Heat transmission by convection occurs with the transfer of heat from the hot outer surface of the oil radiator to the air particles which surround it.
As the air particles receive heat, they move in a substantially vertical direction and are replaced by colder particles to be heated.
From what has been described above it can be seen that the surface temperature of known radiators is practically equal to the temperature of the hot fluid which circulates inside them.
Therefore, in this situation the surface temperature of an oil radiator can be so high that it might cause, in case of contact, burns on the skin of persons.
Therefore, according to the currently applicable statutory provisions on the subject, the surface temperature of an oil radiator must not be high enough to cause possible skin burns.
In order to lower the surface temperature of an oil radiator it is possible to keep the temperature of the fluid inside it within certain values. However the lowering of the temperature of the fluid of the oil radiator would entail, as can be easily understood, the simultaneous reduction of the heating power of the unit.
It should be furthermore noted that the particular blade-like configuration of the radiating elements of known radiators is highly dangerous, especially for children, in case of possible violent impacts against said elements.